The lungs, along with the heart, sustain life with every breath. Hence, diseases of the lung are a serious health concern. Lung diseases can arise due to inflammatory, infectious, genetic and environmental causes. Accurate diagnosis is the key to effective treatment of lung disease.
Asthma
The U.S. Centers for Disease Control and Prevention (CDC) reports 16.4 million adults and 7.0 million children in the United States were living with asthma in 2008. Asthma is a disease of the airways wherein different triggers cause temporary constriction producing shortness of breath, wheezing and cough. Allergens are a common asthma trigger, although many people with asthma do not have allergies. Environmental and occupational exposures, medications, infections and emotional stress are also possible triggers for the hyperreactive airway response of an asthma attack.
Acute Bronchitis
Acute bronchitis is an infection of the upper airways of the lungs, which causes airway swelling, increased mucus production and cough. Viruses are the most common cause of acute bronchitis. Bacteria are less common causative agents, and fungal bronchitis is rare. Acute bronchitis is a self-limited illness that typically clears on its own, just as a cold does.
Chronic Obstructive Bronchitis
In contrast to acute bronchitis, chronic obstructive bronchitis is a noninfectious illness. It is a form of chronic obstructive pulmonary disease, also known as COPD. The disease is the result of chronic inflammation of the upper airways, which results in overproduction of mucus and obstructive airway swelling. The illness is characterized by a chronic cough that produces phlegm and lasts at least 3 months in 2 consecutive years. Cigarette smoking is the most common cause of chronic obstructive bronchitis.
Cystic Fibrosis
Cystic fibrosis (CF) is an inherited disorder of the glands of the lungs and gastrointestinal tract (including the pancreas), and the sweat glands. Although CF is not limited to the lungs, CF-related lung disease is a prominent feature of the disease. The overwhelming majority of people with CF are diagnosed in childhood. Cough is the typical presenting symptom. CF genes cause abnormally thick lung mucus, which does not clear from the airways as normal lung mucus does. Repeated, severe lung infections occur causing progressive lung damage. In severe cases, lung transplantation is required.
Emphysema
Emphysema is a form of COPD. The air sacs--where gas exchange occurs--are damaged by chronic inflammation. As individual air sac walls are damaged, the air sacs merge. The resulting enlarged, scarred air spaces cannot effectively conduct gas exchange and are unable to hold the airways open normally. The obstruction of airflow causes shortness of breath and makes it physically more difficult to breathe. Cigarette smoking is the most common cause of emphysema.
Pneumonia
Pneumonia is an infection of the air sacs and matrix tissue of the lungs (the interstitium). Viruses, bacteria and uncommonly fungi can be the causative agents. Shortness of breath, productive cough, chest pain, fever and a sense of unwellness are common symptoms. Pneumonia can range from mild to severe depending on the extent of infection, the causative agent, and your overall health. CDC reports more than 55,000 Americans died of pneumonia in 2006.
References
- "Harrison's Principles of Internal Medicine, 16th Edition"; Dennis L. Kasper, M.D., et al, Editors; 2004
- U.S. Centers for Disease Control and Prevention: Asthma FastStats
- Merck Manual: Asthma
- American Academy of Family Physicians: Acute Bronchitis
- U.S. Centers for Disease Control and Prevention: Bronchitis
